Hi, my home assistant is reconnecting (restarting) every 5 minutes after a core update.
I can’t use backup-restore in HA, so how can I install my old backup ?
Do I have to start from scratch by installing everything?
Just do a fresh install and on the first screen you can upload your backup and restore it.
Thanks, I updated my Home assistant core, and something went wrong. My raspberry pi is reconnecting every 4-5 minutes. Is there an other solution to reinstall my old backup that I don’t have to start from scratch?
You don’t “start from scratch” you are simply reinstalling the OS and restoring your backup which will restore all your integrations and settings. I can’t guide you in fixing your rPi because it could be a hundred things and, in the end, it takes 20 minutes for you to use Balena to etch a new image to your SD and see if it works versus hours of back and forth on here 
Thanks for your help. I’am new in HA and have no experience how to solve a problem.
If you have a backup downloaded to your computer then re-etching HA onto your SD card (or hard drive, whichever) is pretty fast. You could try to diagnose your issue but if you are on an SD card they do have a much higher failure rate than an SSD drive would, so your SD could be smoked or it could be something in your HA itself. The restoration should answer those questions.
Also, you could hook up a monitor and keyboard to your rPi and see what the console says when you try to start up HA.
I’am using a ssd drive, so I will start with balena image and then I know what to do. I did it already several times, but I had no backup. Now I make everyday a backup. So it will be easier, I think.
You can also just fully start from scratch for a few minutes to make sure things work and THEN restore your backup, this might give you a better sample.